The present invention relates to a crawler travelling apparatus in which a crawler having crawler links is windingly laid over the driving wheel and the take-up wheel, guide wheels are disposed at the frame for guiding the lower travel portion of the crawler and the lateral outer portions of these guide wheels are covered by an earth and sand protect cover.
In order to prevent earth and sand from flowing into the crawler guide wheels, covers have been disposed at the lateral outer portions of the guide wheels. However, when earth and sand once flowed into the insides of these covers, such covers themselves have hindered the outflow of earth and sand, and such earth and sand have subsequently accumulated there in succession and intruded further into the driving wheels. On the other hand, earth and sand have entered the crawler links directly from the spaces between the covers and the driving wheels, and such earth and sand have further intruded into the driving wheels, thus causing the driving wheels to run onto the crawler links and the drive load to be increased.